The Development On The Detecting And Controlling Circuit Of Semiactive Laser Guidance Seeker

The semiactive laser guidance weapon simulation system plays an important role in the laser guidance weapons developing process, for it can save the massive developing funds and experimental time. It also plays an important role in application simulating and in training.A simulated semiactive laser guidance seeker was designed based on the PL-2 missile seeker in the paper, and that the circuit of the seeker was developed, which is the stiff foundation of developing the semiactive laser guidance weapon simulation system.The gyroscope is the key device for stabilizing, scanning and tracking in the seeker. The work mechanism of the gyroscope and especially the precession theory in the seeker is illustrated detailedly through analyzing the PL-2 missile seeker's structure. The gyroscope electric circuit, including the gyroscope's rotary circuit,the gyroscope's precessional circuit and the gyro shaft position detecting circuit, was designed according to the gyroscope's work mechanism. The gyroscope electric circuit was fully tested and worked well.The target-detecting circuit was designed and the infrared photo detecting element in the PL-2 missile s eeker was r eplaced with a four-quadrant photo detector, therefor, the simulated seeker can work with the 650nm laser. A low noise photoelectric circuit was designed to detect the guiding laser pulse signal, and in order to enhance the system signal to noise ratio, a correlated synchronal detecting scheme was introduced. Some research work was done to identify the linearity characteristic of four-quadrant photo detector.A MCU was used to acquire the photo detector data. The periphery circuit of MCU and the MCU program was designed. The MCU controls the gyroscope. Searching and tracking of the guiding laser facula was achieved.In the paper, controlling the phase-shift of precession signal with the method of digtal phase-locked frequency multiplication and the conveniently controlling direction of the gyroscope precession was realized. The problem of controlling direction of the gyroscope precession while searching and tracking of the target was completely solved. Using the digtal phase-shift in order to control the direction of precession conveniently is innovative, which play a key part in the developing simulation seeker.